Distance: 10.8 km
Duration (average) : 2h30
Level: Blue level - Moderate
Elevation: 184 D +
Departure: Chirens
Yellow paint markings and directional posts at the main intersections (if there is no marking, stay on the main road)
In the countryside
Recommended period (s): Autumn, Summer, Winter, Spring
Road crossing (D1075) Sections of road without shoulder (50m at Le Gayet and 400m on the D82 before Arsenal)


You will find yourself at the bottom of the ancient lake of Chirens which, after the ice melted around 15 000 years ago, was filled with sediment and peat to become a marsh. Beautiful views over the ancient glacial valley of the Val d'Ainan.

These marshes today extend over 380 hectares between the foothills of Chartreuse and Lake Paladru.
Wet meadows, reed beds, pastures, cereal fields and afforestation ... It is a mosaic of environments with great floristic diversity. A rich variety of plants flourish on the site such as Orchids and species specific to wetlands such as willows or reeds. The path of the Dragonflies developed by the Department offers the discovery.

Additional information : Shops in the city center Hike passable all year round but to be preferred in spring if you wish to admire the biodiversity of the marshes

History, culture and heritage: 
Take advantage of your visit to Chirens to visit the Benedictine Priory of Chirens and its remarkable XNUMXth century Romanesque apse.

Topo/step by step: 
Stages of the circuit with the name of the signposts to follow: - Chirens - Beaudiné Info May 2022: works do not allow you to pass on the route between Beaudiné and Jolis. You have to go to the roundabout, turn right and you arrive at the Priory. At the Le Prieuré post, follow Le Gayet then Les Jolis. - Les Jolis - Les Brosses - Le Ruibet - La Garangère - La Courriaz - Clermont - La Reviriaz - L'Arsenal - L'Anvers - Beaudiné - Chirens

Tips and Suggestions: 
Pedestrian map of the Pays Voironnais at 1/25000 (on sale at 5 € in the reception offices of Voiron and Lac de Paladru)

Sustainable tourism : 
Mother Nature thanks you for leaving with your waste, she digests it badly! Respect cultures and private properties by staying on marked trails.

to report a problem



Free access.

Equipments & services


  • Parking

Home of animals

  • Animals accepted: Yes
  • Dogs on a leash


Church parking lot

Contact Informations

The marshes of Chirens

Church parking

38850 Chiren's

Getting to the starting point